There is no ambiguity about what devices are connected in a multimedia system when the attachment is via wire. However, connectivity for wireless devices requires a means to specify valid/authorized communication combinations. Each device must be able to recognize a legitimate partner and have shared secrets used to safeguard high value content. This pairing information is usually established as a genetic imprint at the factory or can be done as part of an adoption procedure in the field.
Hard pairing at the factory makes field repairs difficult and may preclude support for multiple pairings. Manual pairing by the end user can be complicated, cumbersome, annoying and subject to human error. Manual pairing is also vulnerable to security compromises. Any pairing needs to be as secure a process as HDCP.